1. Field of the Invention
This invention relates to a process for the manufacture of a tannin based polymer flocculant which does not gel and which remains stable over a period of several months.
2. Description of the Previously Published Art
British Pat. No. 899,721 discloses a process for flocculation of suspensions such as sewage, industrial waste and natural water in which a flocculating agent is applied comprising the reaction product between a tannin, formaldehyde and an amino or ammonium compound. This patent is directed to the new use of this reaction product and provides no detailed discussion of how the reaction product is to be formed nor does it provide any example of making the reaction product. The disclosed advantage of using the flocculating agent is that it does not effect the pH of the suspension solution and that the flocculating agents do not affect the dissolved inorganic solids content of the final water.
Merely reacting these three ingredients disclosed in the British patent forms a reaction product which tends to form a gel; it does not remain in the liquid form for substantial periods of time.
3. Objects of the Invention
It is an object of this invention to produce a tannin based polymer flocculant which will not gel or solidify over a period of several months.
It is a further object of this invention to react tannin, an amino compound and an aldehyde to form a flocculant which is made under such controlled reaction conditions that a high solids flocculant is obtained which does not gel or solidify over a period of several months.
It is a further object of this invention to produce a tannin based polymer flocculant which when used in water purification and demulsification and which continues to provide commercially acceptable performance after being stored for relatively long periods of time.
It is a further object of this invention to produce a tannin based polymer flocculant which is made by monitoring the intermediate viscosity of the reaction product so as to obtain a final product with a long shelf life.
It is a further object of this invention to treat wastewater by adding this unique tannin based polymer flocculant which has a long shelf life.
These and further objects will become apparent as the description of the invention proceeds.